Refrigerant distributor



Nov. 19, 1940. J. LEAR 2,222,216

REFR I GERANT DI STRIBUT OR 1 Original Filed March 4, 1937 INVENT R MBZW ATTORNEY Patented Nov. 19, 1940 UNITED STATES REFRIGERANTDISTRIBUTOR Joseph D. Lear, Buifalo, N. Y., assignor to FeddersManufacturing Company, Inc., Buffalo, N. Y.

Original application March 4, 1937, Serial No. 129,019. Divided and thisapplication February 14, 1939, Serial No. 256,273

6 Claims.

This invention relates to refrigeration systems, and it has particularreference to the rovision of means for distributing liquid refrigerantto a plurality of expansion coils.

The invention is applicable in systems where a plurality of separaterefrigeration coils are'supplied from a. single source through an inletmanifold, and it consists of a distributor which apportions therefrigerant supply to the feed conduits which lead to the several coils.In the embodiment of the invention illustrated herein, there is provideda unit with a plurality of ports which, through valve structures, may bevaried to suit the demands of the several coils. Undesirableinequalities or equalities of feeding may therefore be eliminated.

The invention is more specifically described in the accompanyingspecification, reference being had to the drawing, wherein:

Fig. 1 is a side elevation of a distributor unit with portions shown invertical section. An associatedrefrigerant coil unit is showndiagrammatically.

Fig. 2 is a plan thereof.

Fig. 3 is an enlarged fragmentary section on the line 3-3 of Fig. 1.

Fig. 4 is a side elevation of a control valve.

In Fig. l a feed or distributor unit I is shown organized with arefrigerant evaporator unit I l of a well known type consisting offinned tube coils l2, l3, l4, vertical rows and having inlet'or feedtubes 12a, l3a, Ila, l5a, Ilia, Ila leading to the control unit Ill. Theoutlet terminals of the coils lead to a common discharge header I 8,which communicates with the suction sideof a refrigeration systemthrough a suction pipe 20,

The unit H is mounted in an air duct 2!, and the stream of air which isforced therethrough passes through the successive coil structures and isprogressively. cooled to the desired temperaill ture. As is well knownin the art, the first coil l1 impinged by the air bears the heaviestrefrigerating load, which load isdiminished progressively inthesucceeding coils, and accordingly the coils will require a directlyproportional supply of refrigerant, which, in the present invention, isaccurately metered to the-feed tubes through the distributor unit III.

50 is fitted over and brazed to the upper flange 23.

l5, l6, 11, disposed in parallel The unit [0 includes a housingfabricated of The open end of the shell is subsequently spun over andbrazed to the lower flang 24, as indicated by the numeral 28, to form asealed annular reservoir or compartment 30 about the body 22. Thereservoir is supplied with refrigerant 5 through an inlet pipe 29 whichis fitted in a drilled inlet boss 3| in the flange 24. The pipe may leadto any of the well known control valve units used inrefrigerationsystems for controls ling the quantity of refrigerantdirected to the coils. j For exemplary purposes, a thermostaticexpansion valve V is shown interposed in the pipe line 9.

The body is drilled to provide six equally spaced -vertical formations,each comprising an opening 18 33 for receiving one of the feed tubes, acommunicating vertical valve chamber 34, a valve stem opening 35, and atapped hole 36. The body is slotted to provide elongated vertical ports3"! each leading into a valve chamber 34, and thus pro- 20 vidingcommunication between the reservoir and the feed tubes of the evaporatorunit Ii.

The port areas are controlled by manually operable valve devices whichmay be of any of the numerous forms known in the art. I prefer, how- :5ever, to utilize a cylindrical valve 40, which is formed with aflattened side 4|. Each valve is rotatably mounted within a valvechamber 34 and it is formed with astem 42 of reduced diameter whichprojects through the opening 35. 30 The tapped hole 36 receives a nut 43which retains a packing ring 44 in tight engagement with the stem 42,and thus prevents gas escape about the stem. The projecting portion ofeach stem receives an operating handle 46 which overlies u an escutcheonplate 41 which. is soldered to the end 21 of the shell 25. The plate 41is formed with dial markings 48 for each handle 46 to indicate the openand closed position of the valve.

When it is possible to place the unit I0 above the level of the coilunit H, I have found it advantageous to reduce the head pressurein thereservoir 30 and valve chambers 34, so that a. close simulation of agravity feed through the valves is obtained. This is eifected byproviding a diametricai hole 50 in the body 22, which communicates withthe upper extremity of the reservoir 30. This hole communicates with avertical hole 5| which receives a gas escape tube 52 leading to thedischarge header l8. Thus, gases r accumulating in the reservoir 30 aredischarged directly into the header l8, and accordingly the pressure inthe reservoir is reduced so that a gravity flow of the liquidrefrigerant is obtained. .In .othertypes of installations, it may be dsirr nevertheless permits'of independentsetting of It will be apparentthat after a preliminary setting of the valves on the basis of thecomputed capacity of the various coils, a more accurate setting thereofmay be obtained by observation of the sweat or dew points on the coils,so

that under constant air flow conditions the coils may operate withmaximum efliciency. In the drawing, the'valve of the last coil 12 isclosed, so that the coil is rendered completely inoperative, while theremaining coils, starting with the coil H, are supplied withprogressively diminishing volumes of refrigerant. Thus, not only may thecoils be supplied with precise volumes of refrigerant, but any desirednumber of coils may be shut down when the operation of the system undera reduced load is deemed economical.

The structure of the valves and ports is such that the refrigerantescapes from the reservoir 30 through narrow, vertical slits, and, as aresult, the liquid refrigerant will continue to rise in the reservoiruntil it attains a level where the covered port areas are substantiallyequal to the orifice area of the escape port of the thermostaticexpansion valve V, which supplies the reservoir. In view of theproportional characteristics of the port openings, it will be apparentthat even if the unit III is installed a few-degrees out of a truevertical position, the error reflected on the ports will be extremelysmall.

The applicability and value of the invention will be apparent byconsidering the conditions which arise in feeding refrigerant to aplurality of coil passages from a common source. tofore, it wascustomary to provide each coil passagewith its own thermostaticexpansion valver Due, however, to initial cost, andvthe difficulty ofbalancing-a large number of thermo-' static valves against eachother,this method has met with universal criticism. Recourse was then made tostatic distributors connected between the coil passages and thedischarge side of a single valve. The object of a substantial number ofdesigns along this line has been to equalize the flow .of refrigerant toeach coll,- thus,'i1 there were six coil passages, the distributor wouldbe provided with six equalsized discharge ports. 4

. However, experience hasshown that this proposal does not give theresults desired. One reason is that a. flowing and boiling mass ofrefrigerant will not.readily divide itself uniformly in passing througha number of simple oriflces, such as holes drilled in a plate. Anotherreason is that many' coils .arer'so installed that the. heat load on onesection is not equal to the heat load on another, and thereforeabsolutely uniform distribution of refrigerant, if obtained in the flrstinstance, would not be wanted. When-.

. ever the quantity ofrefrigerant is divided and proportioned improperlywith respect to the heat load on the several coils, the coil efliciencymust be reduced to the effectiveness of the most inemcient section, toavoid flooding of the com- The necessity for independent thermostaticvalves,

7 the several ports leading to the coil sections,

after the unit isinstalled. By observing the degree of superheat on thesuction side of each unit, and adjusting the valve handles 4' as ing2,222,210 able to reduce the eifective area of the tube 52 Here--present invention, while the dicated, each coil section may then bebrought to the same degree of eifectiveness, and irregularities due tovariations in internal resistance, port apertures, and coil loading maybe compensated for.

The present application is a division of my copending' applicationSerial No. 129,019, filed March 4, 1937. It will be understood thatwhile the invention has been described with reference to a singleembodiment, its novel and useful features may be embodied in other formsand arrangements, and therefore it is intended that the scope of theinvention should be determined by reference to the following claims.

"I claim: I

l. A distributor device for supplying refrigerant to a plurality ofcooling coils comprising a housing including a compartment connected toa'refrigerant supply source, a plurality of vertically disposed valvechambers in the housing, one end of each chamber being connected to afeed conduit for a cooling coil, vertical ports in the housingconnecting each chamber with said compartment, an elongated valve ineach chamber disposed therein to control the port area, each valvehaving a stem extending through the housing and supplied with anadjusting lever.

2. A distributor device for supplying refrigerant to a plurality ofcooling coils comprising a housing including a compartment connected toa refrigerant supply source, a plurality of vertically disposedcylindrical valve chambers in said housing, one end of each chamberbeing connected to a feed conduit for a cooling coil, a vertical slot inthe housing entering each chamher and constituting ports forconnectingthe chambers to said compartment, a cylindrical valverotatably mounted in each valve chamber and formed withan axialflattened side, each ,valve having a stem extending through thehous ingand supplied with an adjusting -lever.

3. A distributor device for supplying refrigerant to a plurality ofcooling coils comprising a.

housing including a compartment connected to a refrigerant supplysource, a pluralityof vertically-disposed cylindrical valve chambers insaid housing, one end of each chamber being connected'to a feed conduitfor a cooling coil, a

"vertical slot in the housing entering each chamher and constitutingports for connecting the chambers to said compartment, a-cylindricalvalve rotatably mounted in each valve chamber and formed with an axialflattened side, each valve having a'stem extending through the housingand supplied'with an adjusting lever, and indicia groups formed on theexterior of the housing for cooperation with each lever.

4. A distributor device for supplying refriger-' ant to a plurality ofcooling coils comprising a ,vertically disposed bodyhaving a --circularra-' dial flange on its lower extremity and a cup shaped shell having anopening inits end wall through which the upperextremity of the bodyprojects, the remainder of the shell enclosing the body with the openend of the shell secured to saidflange, a plurality of vertically disvalve chambers in said body, the lower end of each chamber beingconnected to a feed conduit for a cooling coil, said body being formedwith vertical port slots each establishing communication between achamber and the space enclosed by the shell, an elongated valve in eachchamber disposed therein to control the portmeaehvalvehavingastcmextendingthmugh the body and supplied with anadjusting lever.

5. In a refrigeration system having a plurality of independent coolingcoils and a refrigerant supply conduit including an automatic controlvalve therein, -a distributor comprising a housing adapted to receivevolumes of refrigerant from said conduit under control of the controlvalve, a plurality of discharge ports formed in the housing, each ofsaid ports being adapted to be connected to supply one of said coolingcoils, and independently adjustable valve means for varying theelfective opening of eachyof said ports so that refrigerant supplies tothe housing may be selectively apportioned to the coils.

6. In a refrigeration system having a plurality of cooling coils and arefrigerant supply conduit including an automatic control valve therein,a distributor comprising a housing adapted to receive volumes ofrefrigerant from said conduit under control of the control valve,distributor conduits communicating with the housing and each beingadapted for connection to one of the coils, port means in the housingfor admitting refrigerant from the housing to each of the conduits, andmanually adjustable valve means for controlling the proportionatequantity of refrigerant passing through each of said port means intosaid coils, whereby by manual setting of said valve means the quantityof refrigerant supplied to the housing by the automatic control valvemay be proportioned to the heat load on each coil and to the totalquantity of refrigerant thus supplied.

JOSEPH D. LEAR.

